Charging mat



FIG. 1 is a perspective view of a charging mat, showing our new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a side view thereof;

FIG. 5 is another side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines present in the figures are for the purpose of illustrating portions of the article which form no part of the claimed design. 

CLAIM The ornamental design for a charging mat, as shown and described. 